package com.webserver.http;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.net.Socket;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;

/**
 * 响应对象
 * 该类的每一个实例用于表示服务端给客户端发送的一个HTTP响应内容。每个响应由三部分构成：
 * 状态行，响应头，响应正文
 */
public class HttpResponse {
    //状态行相关信息
    private int statusCode = 200;//默认值200
    private String statusReason = "OK";//默认值OK

    //响应头相关信息
    private Map<String,String>headers=new HashMap<>();


    private File entity;//响应正文对应的实体文件

    private Socket socket;

    public HttpResponse(Socket socket) {
        this.socket = socket;
    }

    public void flush() throws IOException {
        //3.1发送状态行
        sendStatusLine();
        //3.2发送响应头
        sendHeaders();
        //3.3发送响应正文
        snedContent();
    }

    private void sendStatusLine() throws IOException {
        //3.1发送状态行
        String line = "HTTP/1.1" + " " + statusCode + " " + statusReason;
        println(line);
    }

    private void sendHeaders() throws IOException {
        //3.2发送响应头
        /*
        Map headers
        key              value
        Content-Type     text/html
        Content-Length   1101
        XXXXX            XXXX
         */
        Set<Map.Entry<String,String>>entrySet=headers.entrySet();
        for (Map.Entry<String,String> e:entrySet){
            String name=e.getKey();         //响应头的名字
            String value=e.getValue();      //响应头对应的值
            String line=name+": "+value;
            println(line);
        }

        //单独发送CRLF表示响应头发送完毕
        println("");
    }

    private void snedContent() throws IOException {
        //3.3发送响应正文
        try (//利用异常处理机制的自动关闭特性，确保文件流使用后被关闭
                FileInputStream fis = new FileInputStream(entity);
                ) {
            OutputStream out = socket.getOutputStream();
            byte[] data = new byte[1024 * 10];//10kb
            int len;               //每次实际读取到的字节数量
            while ((len = fis.read(data)) != -1) {
                out.write(data, 0, len);
            }
        }


    }

    private void println(String line) throws IOException {
        OutputStream out = socket.getOutputStream();

        byte[] data = line.getBytes("ISO8859-1");
        out.write(data);
        out.write(13);//发送一个回车符
        out.write(10);//发送一个换行符
    }

    public int getStatusCode() {
        return statusCode;
    }

    public void setStatusCode(int statusCode) {
        this.statusCode = statusCode;
    }

    public String getStatusReason() {
        return statusReason;
    }

    public void setStatusReason(String statusReason) {
        this.statusReason = statusReason;
    }

    public File getEntity() {
        return entity;
    }

    /**
     * 添加响应正文对应的实体文件
     * 添加该文件的同时会根据实体文件自动添加来攻说明正文的响应头Content-Type和Content-Length
     * @param entity
     */

    public void setEntity(File entity) {
        this.entity = entity;

/*      设置响应头
         1.根据entity获取该正文文件的文件名
         2.根据文件名获取到资源后缀名
         3.根据资源后缀名设置Content-Type的值
         html          text/html
css           text/css
js            application/javascript
png           image/png
gif           image/gif
jpg           image/jpeg
 */

        String[] fileNames=entity.getName().split("\\.");
        String fileLastName=fileNames[fileNames.length-1];
        Map<String,String> mimeMapp = new HashMap<>();
//        mimeMapp.put("html","text/html");
//        mimeMapp.put("css","text/css");
//        mimeMapp.put("js","application/javascript");
//        mimeMapp.put("png","image/png");
//        mimeMapp.put("gif","image/gif");
//        mimeMapp.put("jpg","image/jpeg");
        String type=HttpContext.getMimeMapping(fileLastName);

        String typeValue=mimeMapp.get(fileLastName);

        putHeader("Content-Type",typeValue);
        putHeader("Content-Length",entity.length()+"");
    }

    /**
     * 添加一个要发送的响应头
     * @param name
     * @param value
     */
    public void putHeader(String name,String value){
        this.headers.put(name,value);
    }
}
